Hemichordates exhibit

Options

A. internal fertilisation and direct development
B. internal fertilisation and indirect development
C. external fertilisation and indirect development
D. external fertilisation and direct development

Answer

### Step-by-Step Solution:

1. **Understanding Hemichordates**:
- Hemichordates are a group of marine animals that exhibit specific characteristics. They are known for having a true body cavity, an unsegmented body, bilateral symmetry, and being triploblastic.

2. **Fertilization in Hemichordates**:
- The fertilization process in hemichordates occurs externally. This means that the eggs and sperm are released into the seawater, where fertilization takes place outside the body of the organism.

3. **Development in Hemichordates**:
- Following external fertilization, the development of hemichordates is classified as indirect. This indicates that the developing embryos go through a larval stage before maturing into adults.

4. **Choosing the Correct Option**:
- Based on the above information, we can conclude that hemichordates exhibit external fertilization and indirect development. Therefore, the correct answer is option three: "external fertilization and indirect development."

### Final Answer:
Hemichordates exhibit external fertilization and indirect development.

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